Substrate for liquid crystal display, liquid crystal display having the same and method of manufacturing the same

ABSTRACT

It is an object of the invention to provide a substrate for a liquid crystal display, a liquid crystal display having the same, and a method of manufacturing the same which make it possible to provide a display having high luminance and preferable display characteristics to be used in display sections of information apparatuses and the like. Each pixel is defined by gate bus lines extending in the horizontal direction and drain bus lines extending in the vertical direction. TFTs are formed in the vicinity of intersections between the bus lines, and resin overlap sections for shielding the TFTs from light are formed above the same. No black matrix is formed on a common electrode substrate which is provided in a face-to-face relationship with a TFT substrate, and the bus lines and the resin overlap sections formed on the TFT substrate function as a black matrix.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a liquid crystal displaysubstrate that forms a part of a liquid crystal display used in adisplay section of an information apparatus or the like, a liquidcrystal display having the same and a method of manufacturing the same.

[0003] 2. Description of the Related Art

[0004] In general, a liquid crystal display comprises two substrateshaving a transparent electrode and a liquid crystal sealed between thetwo substrates. The liquid crystal is driven by applying a voltagebetween the two transparent electrodes to control the transmittance oflight through the liquid crystal, which allows a desired image to bedisplayed. An active matrix liquid crystal display is comprised of a TFTsubstrate having thin film transistors (TFTs) for switching respectivepixels formed thereon and a common electrode substrate having a commonelectrode formed thereon. A recent increase in the need for liquidcrystal displays has resulted in diverse requirements for liquid crystaldisplays. In particular, there are strong demands for improvements ofviewing angle characteristics and display quality, and VA (verticallyaligned) mode liquid crystal displays are regarded as promising meansfor satisfying such demands.

[0005] A VA mode liquid crystal display is comprised of two substrateswhich have been subjected to a vertically aligning process on surfacesthereof facing each other and a liquid crystal having negativedielectric anisotropy sealed between the two substrates. The liquidcrystal molecules of the liquid crystal are characterized by homeotropicalignment and are aligned substantially perpendicularly to the substratesurfaces when no voltage is applied between the electrodes. They arealigned substantially in parallel with the substrate surfaces when apredetermined voltage is applied between the electrodes and are alignedat an angle to the substrate surfaces when a voltage lower than saidvoltage is applied.

[0006] MVA (multi-domain vertical alignment) type liquid crystaldisplays are recently attracting attention from the viewpoint ofimprovement of viewing angle characteristics of liquid crystal displays.In the case of an MVA type display, a pixel is divided into a pluralityof domains using alignment regulating structures such as linearprotrusions and slits provided on two substrates to achieve separatealignment in which liquid crystal molecules are tilted in a differentdirection in each domain.

[0007]FIG. 35 shows a configuration of an MVA type liquid crystaldisplay and shows an arrangement of linear protrusion formed asalignment regulating structures on two substrates. FIG. 35 shows threepixels in red (R), green (G) and blue (B). As shown in FIG. 35, linearprotrusions 104 are formed on a TFT substrate 108 and linear protrusions106 are formed on a common electrode substrate 110. The linearprotrusions 104 and 106 are formed at an angle to the pixels. Each ofthe R, G and B pixel regions is defined by a black matrix (BM) 102formed on the common electrode substrate 110. The BM 102 serves as alight shield for a storage capacity bus line extending across each pixelsubstantially in the middle thereof and a storage capacity electrodelocated above the same (both of which are not shown).

[0008]FIG. 36 is a sectional view of the liquid crystal display takenalong the line X-X in FIG. 35. As shown in FIG. 36, the TFT substrate108 has a pixel electrode 114 formed for each pixel on a glass substrate112. The figure omits an insulation film, drain bus lines, a protectivefilm, and so on formed on the glass substrate 112. The linearprotrusions 104 are formed on the pixel electrodes 114. A verticalalignment film 116 is formed to cover the pixel electrodes 114 andlinear protrusions 104 entirely. The common electrode substrate 110 hasthe BM 102 formed on the glass substrate 112. Resin colorfilter(CF)layers R, G and B (FIG. 36 shows the filters G and B only) areformed in each of the pixel regions defined by the BM 102 on the glasssubstrate 112. A common electrode 118 is formed on the region CF layersR, G and B, and the linear protrusions 106 are formed on the commonelectrode 118. Further, a vertical alignment film 116 is formed to coverthe common electrode 118 and linear protrusions 106 entirely. Sphericalspacers 122 made of plastic or glass for maintaining a gap (cell gap)between the substrates 108 and 110 and a liquid crystal LC is sealedbetween the TFT substrate 108 and common electrode substrate 110.

[0009]FIG. 37 is a sectional view of the liquid crystal display takenalong the line Y-Y in FIG. 35, and it shows a state of the liquidcrystal LC when no voltage is applied. As shown in FIG. 37, liquidcrystal molecules (represented by columns in the figure) are alignedsubstantially perpendicularly to the vertical alignment films 116 on thetwo substrates 108 and 110. Therefore, liquid crystal molecules in theregions where the linear protrusions 104 and 106 are formed are alignedsubstantially perpendicularly to the surface of the linear protrusions104 and 106 and are aligned at a slight angle to the normal of the twosubstrates 108 and 110. Since polarizers (not shown) are provided in acrossed Nicols configuration outside the two substrates 108 and 110,black display is achieved when no voltage is applied.

[0010]FIG. 38 is a sectional view of the liquid crystal display takenalong the line Y-Y in FIG. 35 similarly to FIG. 37, and it shows a stateof the liquid crystal LC when a voltage is applied. The broken lines inthe figure represent lines of electric force between the pixelelectrodes 114 and common electrode 118. As shown in FIG. 38, when avoltage is applied between the pixel electrodes 114 and common electrode118, the electric field is distorted in the vicinity of the linearprotrusions 104 and 106 which are made of a dielectric material. As aresult, the tilting angles of liquid crystal molecules having negativedielectric anisotropy are regulated, and the tilting angles can becontrolled depending on the field intensity to display gray shades.

[0011] At this time, if the linear protrusions 104 and 106 are providedin linear configurations as shown in FIG. 35, liquid crystal moleculesin the vicinity of the linear protrusions 104 and 106 are tilted in twodirections which are orthogonal to the extending directions of thelinear protrusions 104 and 106, the tilting directions beingsymmetrically defined about the linear protrusions 104 and 106. Sincethe liquid crystal molecules in the vicinity of the linear protrusions104 and 106 are at a slight angle to a direction perpendicular to thetwo substrates 108 and 110 even when no voltage is applied, they arequickly tilted in response to the field intensity. The tiltingdirections of liquid crystal molecules in the neighborhood aresequentially determined in accordance with the behavior of theabove-mentioned liquid crystal molecules, and the tilting angles dependon the field intensity. As a result, alignment separation is achieved atthe linear protrusions 104 and 106.

[0012]FIG. 39 is a sectional view taken along a line Y-Y of a liquidcrystal display as shown in FIG. 35 in which slits 120 are formed inplace of the linear protrusions 104, the figure showing a state of thedisplay when no voltage is applied. As shown in FIG. 39, the slits 120which are alignment regulating structures are formed by removing thepixel electrodes 114. Liquid crystal molecules are aligned substantiallyperpendicularly to the vertical alignment films 116 on the twosubstrates 108 and 110 similarly to the liquid crystal molecules shownin FIG. 37.

[0013]FIG. 40 is a sectional view of the liquid crystal display takenalong the line Y-Y similarly to FIG. 39, and it shows a state of aliquid crystal LC when a voltage is applied. As shown in FIG. 40, linesof electric force substantially similar to those in the regions wherethe linear protrusions 104 are formed as shown in FIG. 38 are formed inthe regions where the slits 120 are formed. As a result, alignmentseparation is achieved about the linear protrusions 106 and slits 120.FIGS. 37 and 40 omit the spherical spacers 122 for maintaining a cellgap.

[0014]FIG. 41 is a sectional view of the liquid crystal display takenalong the line Z-Z in FIG. 35 showing the neighborhood of a drain busline 126. As shown in FIG. 41, the TFT substrate 108 has an insulationfilm 124 covering an entire surface of the glass substrate 112. Thedrain bus line 126 is formed on the insulation film 124. A protectivefilm 128 is formed on the entire surface of the drain bus line 126. Apixel electrode 114 for each pixel is formed on the protective film 128.A black matrix BM 102 is formed on a common electrode substrate 110provided in a face-to-face relationship with the TFT substrate 108 suchthat it serves as a light shield for regions on the TFT substrate 108where no pixel electrode 114 is formed (edges of pixel regions).

[0015] The conventional MVA type liquid crystal display has the problemof darkness of display because of low transmittance of the panel. Thelow panel transmittance is attributable to various factors including areduction in the numerical aperture caused by misalignment between theTFT substrate 108 and common electrode substrate 110, a reduction in thenumerical aperture attributable to the alignment regulating structures(the linear protrusions 104 and 106 or slits 120), and irregularities inthe alignment of the liquid crystal in the vicinity of the sphericalspacers 122.

[0016] Because of significantly improved viewing angle characteristics,MVA type liquid crystal displays are preferably used as monitors forpersonal computers and the like for which high luminance has relativelylow importance. However, in order to use them as display sections of DVD(digital versatile disk) players or televisions for which high luminanceis an important requirement, it is necessary to provide a brighterback-light or to use a special sheet for aligning light-emittingdirections to improve luminance in a particular direction. This hasresulted in the problem of an increase in the manufacturing cost.

[0017] Further, the formation of linear protrusions, an insulationlayer, and so on as alignment regulating structures increasesmanufacturing steps when compared to manufacturing steps for normalsubstrates, which also results in an increase in the manufacturing cost.

SUMMARY OF THE INVENTION

[0018] It is an object of the invention to provide a substrate for aliquid crystal display with which a display having high luminance andpreferable display characteristics can be obtained, a liquid crystaldisplay having the same, and a method for manufacturing the same.

[0019] The above-described object is achieved by a liquid crystaldisplay substrate, characterized in that it comprises a substrate whichsandwiches a liquid crystal having negative dielectric anisotropy incombination with an opposite substrate provided in a face-to-facerelationship, a plurality of gate bus lines formed on the substrate, aplurality of drain bus lines formed on the substrate such that theyintersect the gate bus lines, pixel regions defined by the gate buslines and the drain bus lines, a thin film transistor formed in each ofthe pixel regions, a resin color filter layer formed in each of thepixel regions, a pixel electrode formed in each of the pixel regions,and an alignment regulating structure formed on the substrate forregulating the alignment of the liquid crystal.

[0020] The above-described object is achieved by a liquid crystaldisplay, characterized in that it comprises: a thin film transistorsubstrate including a first substrate, a plurality of bus lines formedon the first substrate such that they intersect each other, pixelregions defined by the bus lines, a thin film transistor formed in eachof the pixel regions, a resin color filter layer formed in each of thepixel regions, and a pixel electrode formed in each of the pixelregions; a common electrode substrate including a second substratedifferent from the first substrate in the thickness or material and acommon electrode formed on the second substrate, the common electrodesubstrate being provided in a face-to-face relationship with the firstsubstrate; and a liquid crystal sealed between the thin film transistorsubstrate and the common electrode substrate.

[0021] Further, the above-described object is achieved by a liquidcrystal display substrate, characterized in that it comprises asubstrate which sandwiches a liquid crystal in combination with anopposite substrate provided in a face-to-face relationship therewith, aplurality of gate bus lines formed on the substrate, a plurality ofdrain bus lines formed on the substrate such that they intersect thegate bus lines, pixel regions defined by the gate bus lines and thedrain bus lines, a thin film transistor formed in each of the pixelregions, a resin color filter layer formed in each of the pixel regions,a pixel electrode formed in each of the pixel regions, and a resin layerformed to cover source and drain electrodes of the thin film transistorand the drain bus lines.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022]FIG. 1 shows a configuration of a liquid crystal display in afirst mode for carrying out the invention;

[0023]FIG. 2 is a sectional view showing a first basic configuration ofa substrate for a liquid crystal display in the first mode for carryingout the invention, a liquid crystal display having the same, and amethod of manufacturing the same;

[0024]FIG. 3 is a sectional view showing a modification of the firstbasic configuration of a substrate for a liquid crystal display in thefirst mode for carrying out the invention, a liquid crystal displayhaving the same, and a method of manufacturing the same;

[0025]FIG. 4 is a sectional view showing a second basic configuration ofa substrate for a liquid crystal display in the first mode for carryingout the invention, a liquid crystal display having the same, and amethod of manufacturing the same;

[0026]FIG. 5 shows a third basic configuration of a substrate for aliquid crystal display in the first mode for carrying out the invention;

[0027]FIGS. 6A and 6B show the third basic configuration of a substratefor a liquid crystal display in the first mode for carrying out theinvention;

[0028]FIG. 7 shows a configuration of a liquid crystal display accordingto Embodiment 1-1 in the first mode for carrying out the invention;

[0029]FIG. 8 is a sectional view showing a configuration of a substratefor a liquid crystal display according to Embodiment 1-1 in the firstmode for carrying out the invention;

[0030]FIG. 9 shows a configuration of a substrate for a liquid crystaldisplay according to Embodiment 1-1 in the first mode for carrying outthe invention;

[0031]FIGS. 10A and 10B are sectional views showing the configuration ofthe substrate for a liquid crystal display according to Embodiment 1-1in the first mode for carrying out the invention;

[0032]FIGS. 11A and 11B are sectional views taken at a manufacturingstep showing a method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0033]FIGS. 12A and 12B are sectional views taken at a manufacturingstep showing the method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0034]FIGS. 13A and 13B are sectional views taken at a manufacturingstep showing the method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0035]FIGS. 14A and 14B are sectional views taken at a manufacturingstep showing the method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0036]FIGS. 15A and 15B are sectional views taken at a manufacturingstep showing the method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0037]FIGS. 16A and 16B are sectional views taken at a manufacturingstep showing the method of manufacturing the substrate for a liquidcrystal display according to Embodiment 1-1 in the first mode forcarrying out the invention;

[0038]FIG. 17 is a sectional view showing a configuration of a liquidcrystal display according to Embodiment 1-2 in the first mode forcarrying out the invention;

[0039]FIG. 18 is a sectional view showing the configuration of theliquid crystal display according to Embodiment 1-2 in the first mode forcarrying out the invention;

[0040]FIG. 19 shows a configuration of a substrate for a liquid crystaldisplay according to Embodiment 1-3 in the first mode for carrying outthe invention;

[0041]FIG. 20 is a sectional view showing the configuration of thesubstrate for a liquid crystal display according to Embodiment 1-3 inthe first mode for carrying out the invention;

[0042]FIG. 21 is a sectional view taken at a manufacturing step showinga method of manufacturing the substrate for a liquid crystal displayaccording to Embodiment 1-3 in the first mode for carrying out theinvention;

[0043]FIG. 22 is a sectional view taken at a manufacturing step showingthe method of manufacturing the substrate for a liquid crystal displayaccording to Embodiment 1-3 in the first mode for carrying out theinvention;

[0044]FIG. 23 shows a configuration of a substrate for a liquid crystaldisplay according to Embodiment 2-1 in a second mode for carrying outthe invention;

[0045]FIG. 24 is a sectional view taken at a manufacturing step showinga configuration of a liquid crystal display according to Embodiment 2-2in the second mode for carrying out the invention;

[0046]FIG. 25 shows a configuration of a liquid crystal displayaccording to Embodiment 3-1 in a third mode for carrying out theinvention;

[0047]FIGS. 26A and 26B are sectional views showing the configuration ofthe liquid crystal display according to Embodiment 3-1 in the third modefor carrying out the invention;

[0048]FIG. 27 shows a method of manufacturing the liquid crystal displayaccording to Embodiment 3-1 in the third mode for carrying out theinvention;

[0049]FIG. 28 shows the method of manufacturing the liquid crystaldisplay according to Embodiment 3-1 in the third mode for carrying outthe invention;

[0050]FIG. 29 shows the method of manufacturing the liquid crystaldisplay according to Embodiment 3-1 in the third mode for carrying outthe invention;

[0051]FIG. 30 shows the method of manufacturing the liquid crystaldisplay according to Embodiment 3-1 in the third mode for carrying outthe invention;

[0052]FIGS. 31A and 31B are sectional views taken at a manufacturingstep showing the method of manufacturing the liquid crystal displayaccording to Embodiment 3-1 in the third mode for carrying out theinvention;

[0053]FIGS. 32A and 32B are sectional views taken at a manufacturingstep showing the method of manufacturing the liquid crystal displayaccording to Embodiment 3-1 in the third mode for carrying out theinvention;

[0054]FIGS. 33A and 33B are sectional views taken at a manufacturingstep showing the method of manufacturing the liquid crystal displayaccording to Embodiment 3-1 in the third mode for carrying out theinvention;

[0055]FIGS. 34A and 34B are sectional views showing a configuration of aliquid crystal display according to Embodiment 3-2 in the third mode forcarrying out the invention;

[0056]FIG. 35 shows a configuration of a conventional liquid crystaldisplay;

[0057]FIG. 36 is a sectional view showing the configuration of theconventional liquid crystal display;

[0058]FIG. 37 is a sectional view showing the configuration of theconventional liquid crystal display;

[0059]FIG. 38 is a sectional view showing the configuration of theconventional liquid crystal display;

[0060]FIG. 39 is a sectional view showing the configuration of theconventional liquid crystal display;

[0061]FIG. 40 is a sectional view showing the configuration of theconventional liquid crystal display;

[0062]FIG. 41 is a sectional view showing the configuration of theconventional liquid crystal display; and

[0063]FIG. 42 is a sectional view showing a modification of thesubstrate for a liquid crystal display according to Embodiment 1-2 inthe first mode for carrying out the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0064] [First Mode for Carrying Out the Invention]

[0065] A description will be made with reference to FIGS. 1 through 22and FIG. 42 on a substrate for a liquid crystal display in a first modefor carrying out the invention, a liquid crystal display having thesame, and a method of manufacturing the same. A first basicconfiguration in the present mode for carrying out the invention will bedescribed with reference to FIGS. 1 and 2. FIG. 1 shows three pixels inR, G and B on a TFT substrate 8. As shown in FIG. 1, the pixels aredefined by gate bus lines 25 extending in the horizontal direction inthe figure and drain bus lines 26 extending in the vertical direction inthe figure. TFTs (no shown) are formed in the vicinity of intersectionsbetween the bus lines 25 and 26. Above the TFTs, in order to preventlight from impinging upon the TFTs, resin overlap sections 32 are formedin which at least two out of resin CF layers R, G and B are overlappedwith each other. In the liquid crystal display in the present mode forcarrying out the invention, no black matrix is formed on a commonelectrode substrate which is provided in a face-to-face relationshipwith the TFT substrate 8, and the bus lines 25 and 26 and the resinoverlap sections 32 formed on the TFT substrate 8 provides the functionof a black matrix. Light can be blocked by forming any one of the resinCF layers R, G and B on the TFTs instead of the resin overlap sections32 shown in FIG. 1.

[0066]FIG. 2 is an illustration showing a first basic configuration of asubstrate for a liquid crystal display in the present mode for carryingout the invention and a liquid crystal display having the same is asectional view of the liquid crystal display taken along the line A-A inFIG. 1. As shown in FIG. 2, the TFT substrate 8 has an insulation film24 formed on a substantially entire surface of a glass substrate 12. Thedrain bus lines 26 are formed on the insulation film 24. The resin CFlayers R, G and B (FIG. 2 shows the layers G and B only) are formed onthe drain bus lines 26 (a CF-on-TFT structure). A pixel electrode 14 foreach pixel is formed on the resin CF layers R, G and B. A commonelectrode substrate 10 provided in a face-to-face relationship with theTFT substrate 8 is comprised of a glass substrate 12 and a commonelectrode 18 formed on an entire surface thereof. No black matrix isformed on the common electrode substrate 10. A vertical alignment film(not shown) is formed to cover the pixel electrode 14 and commonelectrode 18 entirely. A liquid crystal layer LC is sealed between theTFT substrate 8 and common electrode substrate 10.

[0067] In the conventional liquid crystal display shown in FIG. 41, acapacity is formed between the pixel electrode 114 and drain bus line126 with the protective film 128 sandwiched as a dielectric material ifthe pixel electrode 114 is formed such that it extends above the drainbus line 126. It is therefore necessary to provide a predetermined gapextending in parallel with the substrate surface between the pixelelectrode 114 and drain bus line 126.

[0068] On the contrary, in the liquid crystal display in the presentmode for carrying out the invention shown in FIG. 2, the resin CF layersR, G and B are formed between the pixel electrodes 114 and drain buslines 126. Since the resin CF layers R, G and B are applied and formedusing a spin coat process or the like, they can be easily formed with agreat thickness compared to the protective film 128 that is formed usinga CVD (chemical vapor deposition) process. It is therefore possible toreduce any electrostatic capacity generated between the drain bus lines26 and pixel electrodes 14. Since this makes it possible to form thepixel electrodes 14 in an overlapping relationship with the drain buslines 26 in the direction perpendicular to the substrate surface, thereis no need for forming a black matrix on the common electrode substrate10, which improves the numerical aperture. Further, since the drain buslines 26 serve as a black matrix to eliminate any need for providing ablack matrix on the common electrode substrate 10, the number ofmanufacturing steps is reduced. This also eliminates any reduction inthe numerical aperture attributable to misalignment between the TFTsubstrate 8 and common electrode substrate 10.

[0069] The CF-on-TFT structure shown in FIG. 2 is suitable for a TNnormally white mode liquid crystal display in which leakage of light canoccur when black is displayed unless pixel electrodes 14 are formed suchthat edges of the same overlap drain bus lines 26. However, in order tosuppress a capacity formed in a region where a pixel electrode 14 and adrain bus line 26 overlap each other, the resin CF layers R, G and Bmust be formed with a considerably great thickness. This results in aproblem in that the CF-on-TFT structure necessitates a manufacturingprocess that is more complicated than forming the resin CF layers R, Gand B on the opposite substrate. Further, in order to block light withthe drain bus lines 26 reliably (bus line light-blocking), the resin CFlayers R, G and B must be formed such that their edges are accuratelyaligned with the drain bus lines 26. Therefore, in the case of drain buslines with a very small line width, a proximity exposure apparatus whichis normally used for forming the resin CF layers R, G and B may fail toachieve sufficient alignment. On the contrary, the use of a stepper ormirror-projection type aligner having excellent aligning accuracy canresult in an increase in the manufacturing cost of the CF-on-TFTstructure.

[0070]FIG. 3 shows a modification of the first basic configuration shownin FIG. 2. As shown in FIG. 3, the pixel electrodes 14 are formed suchthat predetermined gaps in the direction of the substrate surface arekept between edges of the pixel electrodes 14 and drain bus line 26 inorder to prevent the pixel electrodes 14 from overlapping the drain busline 26 when viewed in the direction perpendicular to the substratesurface. An edge of the resin CF layer G is formed on the drain bus line26, however, an edge of the resin CF layer B is misaligned with the topof the drain bus line 26 because of a shift during patterning. However,in the case of a MVA type normally black mode liquid crystal displaywhich displays black when no voltage is applied, even if a pixelelectrode 14 is formed with a predetermined gap from a drain bus line 26such that they do not overlap each other, the problem of leakage lightwill not occur because such a gap region appears in black when novoltage is applied. Further, since no capacity is generated because nooverlap region is formed between the pixel electrode 14 and drain busline 26, resin CF layers R, G and B can be as thin as desired. Even whenthe resin CF layers R, G and B are formed such that their edges aremisaligned with the top of the drain bus line 26 as shown in FIG. 3, nolight leaks as long as the edges of the resin CF layers R, G and B arecloser to the drain bus line 26 than the edges of the pixel electrodes14. Since this makes it possible to provide a great margin for alignmentduring the patterning of the resin CF layers R, G and B, the CF-on-TFTstructure can be obtained at a low cost using a normal proximityexposure apparatus.

[0071]FIG. 4 shows a second basic configuration of the substrate for aliquid crystal display in the present mode for carrying out theinvention and the liquid crystal display having the same, FIG. 4 showinga sectional view of the liquid crystal display taken along the line B-Bin FIG. 1. As shown in FIG. 4, the liquid crystal display has linearprotrusions 28 as alignment regulating structures formed on the pixelelectrodes 14. The resin CF layers R, B and G are laminated in the sameorder in the vicinity of the intersection between the gate bus line 25and drain bus line 26 to form a resin overlap section 32 to serve as ablack matrix. A protrusion 29 which does not function as an alignmentregulating structure is formed on the resin overlap section 32. Theprotrusion 29 is formed simultaneously with the linear protrusions 28from the same material as that of the latter. The resin overlap section32 between the resin layers forming a part of the TFT substrate 8 andthe protrusion 29 are laminated to form a columnar spacer 30 whichmaintains a call gap between the TFT substrate and the common electrodesubstrate 10 provided in a face-to-face relationship.

[0072] In the second configuration in the present mode for carrying outthe invention, the columnar spacer is formed by laminating the resin CFlayers and so on forming a part of the TFT substrate 8. Since thisreduces the number of manufacturing steps, the manufacturing cost can bereduced. Further, since this makes it possible to reduce leakage oflight and irregularities of alignment that can occur in the vicinity ofdispersed spacers having a spherical configuration or the like,preferable display characteristics can be achieved.

[0073]FIG. 5 shows a third configuration of the substrate for a liquidcrystal display in the present mode for carrying out the invention. Aframe pattern 34 for shielding edges of a display area 38 from light isformed in a frame region 40 of the common electrode substrate 10. Forexample, a cross-shaped alignment mark used for combining the samesubstrate with the TFT substrate 8 (which is not shown in FIGS. 5 and6B) in a face-to-face relationship is formed outside the frame region40.

[0074]FIG. 6A is an enlarged view of the region a of the commonelectrode substrate 10 shown in FIG. 5. FIG. 6B shows a section of thecommon electrode substrate 10 taken along the line C-C in FIG. 6A. Asshown in FIGS. 6A and 6B, a common electrode 18 is formed in the displayarea 38 on the glass substrate 12 and in the frame region 40 at theedges of the display area 38. Linear protrusions 28 are formed on thecommon electrode 18 in the display area 38 at an angle to an edge of thedisplay area 38 using a black resist (black resin) or the like. A framepattern 34 for shielding the edges of the display area 38 from light isformed on the common electrode 18 in the frame region 40 simultaneouslywith the linear protrusions 28 from the same material. An alignment mark36 is formed simultaneously with the linear protrusions 28 from the samematerial on the left side of the frame region 40 in the figures.

[0075] In the third basic configuration in the present mode for carryingout the invention, since the frame pattern 34 and alignment mark 36 areformed simultaneously with alignment regulating structures from the samematerial, the number of steps for manufacturing the common electrodesubstrate 10 is reduced to allow a reduction in the manufacturing cost.

[0076] The substrate for a liquid crystal display in the present modefor carrying out the invention and the liquid crystal display having thesame will now be more specifically described with reference toEmbodiments 1-1, 1-2 and 1-3.

[0077] (Embodiment 1-1)

[0078] A description will now be made with reference to FIGS. 7 through16B on a substrate for a liquid crystal display according to Embodiment1-1, a liquid crystal display having the same, and a method ofmanufacturing the same. FIG. 7 is a conceptual illustration showing aTFT substrate 8 and a common electrode substrate 10 which are combined,FIG. 7 showing three pixels in R, G and B. For example, the liquidcrystal display of the present embodiment is an MVA type liquid crystaldisplay, and FIG. 7 also shows the positions of alignment regulatingstructures. Linear protrusions 28 are formed on the common electrodesubstrate 10 at an angle to edges of the pixel regions. On the TFTsubstrate 8, slits 20 and finer slits 21 extending from the slits 20substantially perpendicularly to the extending direction of the slits 20are formed at an angle to the edges of the pixel regions. A plurality offiner slits 21 are formed at intervals smaller than the intervalsbetween the slits 20 and linear protrusions 28. When alignmentregulating structures are formed at relatively small intervals, liquidcrystal molecules having negative dielectric anisotropy are aligned inparallel with the direction in which the alignment regulating structuresextend. Therefore, the alignment of liquid crystal molecules is morestrongly regulated by forming the finer slits 21 perpendicular to theslits 20.

[0079]FIG. 8 shows a section of the liquid crystal display taken alongthe line D-D in FIG. 7. As shown in FIG. 8, the TFT substrate 8 has aninsulation film 24 formed on an entire surface of a glass substrate 12.Drain bus lines 26 are formed on the insulation film 24. Resin CF layersR, G and B (FIG. 8 shows the layers G and B only) are formed on thedrain bus lines 26. Pixel electrodes 14 and the slits 20 which arecuts-off in a part of the pixel electrodes 14 are formed on the resin CFlayers R, G and B. FIG. 8 omits the finer slits 21. The common electrodesubstrate 10 has a common electrode 18 formed on an entire surface of aglass substrate 12. Linear protrusions 28 are formed on the commonelectrode 18. A vertical alignment film (not shown) is formed on thepixel electrodes 14, common electrode 18, and linear protrusions 28. Aliquid crystal LC having negative dielectric anisotropy is sealedbetween the TFT substrate 8 and common electrode substrate 10.

[0080]FIG. 9 shows a configuration in the vicinity of TFTs on the TFTsubstrate 8 of the present embodiment. As shown in FIG. 9, the TFTsubstrate 8 has a plurality of gate bus lines 25 (FIG. 9 shows only oneof them) extending in the horizontal direction in the figure and theplurality of drain bus lines 26 (FIG. 9 shows three lines) extending inthe vertical direction in the figure across the gate bus lines 25 on aglass substrate 12. TFTs 42 are formed in the vicinity of intersectionsbetween the bus lines 25 and 26. A TFT 42 is comprised of a drainelectrode 44 that is a branch of a drain bus line 26, a source electrode46 provided in a face-to-face relationship with the drain electrode 44with a predetermined gap kept between them, and a part (gate electrode)of a gate bus line 25 which overlaps the drain electrode 44 and sourceelectrode 46. An active semiconductor layer 52 is formed on the gateelectrode, and a channel protection film 48 is formed on the same. Thegate bus lines 25 and drain bus lines 26 define pixel regions, and resinCF layers R, G and B are formed in each of the pixel regions. A pixelelectrode 14 is formed in each of the pixel regions. The pixelelectrodes 14 are formed such that their edges in the horizontaldirection in the figure overlap edges of the drain bus lines 26 whenviewed in the direction perpendicular to the substrate surfaces. FIG. 9omits slits.

[0081]FIG. 10A shows a section of the TFT substrate 8 taken along theline E-E in FIG. 9, and FIG. 10B shows a section of the TFT substrate 8taken along the line F-F in FIG. 9. As shown in FIGS. 10A and 10B, theresin CF layers R, G and B are formed on the TFTs 42 and drain bus lines26. The pixel electrodes 14 are formed on the resin CF layers R, G andB. The pixel electrodes 14 are formed such that their edges overlap theedges of the drain bus lines 26 when viewed in the directionperpendicular to the substrate surfaces.

[0082] A method of manufacturing the liquid crystal display of thepresent embodiment will now be described with reference to FIGS. 1Athrough 16B. FIGS. 1A through 16B are sectional views taken atmanufacturing steps showing the method of manufacturing the liquidcrystal display of the present embodiment. FIGS. 11A, 12A, 13A, 14A, 15Aand 16A show the section of the TFT substrate 8 taken along the line E-Ein FIG. 9, and FIGS. 11B, 12B, 13B, 14B, 15B and 16B show the section ofthe TFT substrate 8 taken along the line F-F in FIG. 9. For example, asshown in FIGS. 11A and 11B, an aluminum (Al) layer having a thickness of100 nm and a titanium (Ti) layer having a thickness of 50 nm are formedin the same order on an entire surface of a glass substrate 12 and arepatterned to form gate bus lines 25. The patterning is carried out usinga photolithographic process in which a predetermined resist pattern isformed on the layers to be patterned; the layers to be patterned areetched using the resist pattern as an etching mask; and the resistpattern is then removed.

[0083] Next, for example, a silicon nitride film (SiN film) having athickness of 350 nm, an a-Si layer 52′ having a thickness of 30 nm, anda SiN film having a thickness of 120 nm are continuously formed as shownin FIGS. 12A and 12B. Then, a channel protection film 48 to serve as anetching stopper is formed on a self-alignment basis by patterning thesame through backside exposure. For example, an n⁺a-Si layer having athickness of 30 nm, a Ti layer having a thickness of 20 nm, an aluminumlayer having a thickness of 75 nm, and a Ti layer having a thickness of40 nm are then formed as shown in FIGS. 13A and 13B and are patternedusing the channel protection film 48 as an etching stopper to form drainelectrodes 44, source electrodes 46, and drain bus lines 26. TFTs 42 arecompleted through the above-described steps.

[0084] Next, as shown in FIGS. 14A and 14B, for example, a red resisthaving a photosensitive pigment dispersed therein is applied to athickness of 3.0 μm and patterned. Thereafter, post-baking is performedto form resin CF layers R in predetermined pixel regions, the layershaving contact holes 50 formed above the source electrodes 46.

[0085] Next, as shown in FIGS. 15A and 15B, for example, a blue resisthaving a photosensitive pigment dispersed therein is applied to athickness of 3.0 μm and patterned. Thereafter, post-baking is performedto form resin CF layers B in predetermined pixel regions. Similarly, asshown in FIGS. 16A and 16B, resin CF layers G are formed inpredetermined pixel regions. Next, an ITO film having a thickness of 70nm for example is formed on the entire surface and patterned to formpixel electrodes 14 such that their edges in the horizontal direction inthe figures overlap edges of the drain bus lines 26 when viewed in thedirection perpendicular to the substrate surfaces. A TFT substrate 8 asshown in FIGS. 9 through 10B is completed through the above-describedsteps.

[0086] While the resin CF layers R, G and B are formed directly onsource/drain forming layers such as the drain electrodes 44, sourceelectrodes 46 and drain bus lines 26 in the present embodiment, aprotective film may be formed on the source/drain forming layers and theresin CF layers R, G and B may be formed on the protective film.Alternatively, a protective film may be formed on the resin CF layers R,G and B, and the pixel electrodes 14 may be formed on the protectivefilm. Obviously, the TFTs 42 and resin CF layers R, G and B may beformed and manufactured using materials and steps other than thosedescribed above.

[0087] Referring to alignment regulating structures, the slits 20 andfiner slits 21 are formed on the TFT substrate 8, and the linearprotrusions 28 are formed on the common electrode substrate 10 in thepresent embodiment. However, they may be used in different combinations.The present embodiment provides effects similar to those achieved withthe above-described first basic configuration.

[0088] (Embodiment 1-2)

[0089] A description will now be made with reference to FIGS. 17, 18 and42 on a substrate for a liquid crystal display according to Embodiment1-2 and a liquid crystal display having the same. FIG. 17 is a sectionalview of the liquid crystal display of the present embodiment showing aconfiguration thereof, FIG. 17 showing a section similar to that shownin FIG. 8. As shown in FIG. 17, the liquid crystal display of thepresent embodiment has dielectric layers 56 which are formed above slits20 in a TFT substrate 8 and which serve as alignment regulatingstructures for improving response characteristics of liquid crystalmolecules to half tones. The dielectric layers 56 are formed from aphotoresist or the like.

[0090]FIG. 18 is a sectional view of the liquid crystal display of thepresent embodiment showing a configuration of the same, FIG. 18 showinga section similar to that shown in FIG. 4. As shown in FIG. 18, in theliquid crystal display of the present embodiment, resin CF layers R, Band G are formed in the same order in the vicinity of intersectionsbetween gate bus lines 25 and drain bus lines 26 on the TFT substrate 8.A protrusion 29 which does not function as an alignment regulatingstructure is formed on a common electrode 18 on a common electrodesubstrate 10. A columnar spacer 30 for maintaining a cell gap is formedby a gate bus line 25 on the TFT substrate 8, an insulation film 24, adrain bus line 26, resin CF layers R, G and B, and the protrusion 29 onthe common electrode substrate 10.

[0091] The columnar spacer 30 is not limited to the above-describedconfiguration and may be constituted by other layers. For example, it ispossible to use a resin layer that is formed simultaneously with thedielectric layers 56 on the resin CF layer B from the same material asthat of the layers 56. In this case, it is not necessary to form theprotrusion 29 on the common electrode substrate 10. The TFTs 42, resinCF layers R, G and B, and so on may be formed and manufactured usingmaterials and steps other than those described above. The alignmentregulating structures respectively formed on the TFT substrate 8 andcommon electrode substrate 10 may be in other combinations. The presentembodiment provides the same effects as those achieved with theabove-described second basic configuration.

[0092]FIG. 42 is a sectional view of the liquid crystal display of thepresent embodiment showing a modification of the same, and FIG. 42 showsa section similar to that shown in FIG. 4. As shown in FIG. 42, in theliquid crystal display of the present modification, a columnar spacer 30is structured by only resin CF layers R, B and G laminated in the sameorder in the vicinity of intersections between gate bus lines 25 anddrain bus lines 26 on the TFT substrate 8. Thus, the columnar spacer 30may be formed using neither the protrusion 29 on the common electrodesubstrate 10 nor the dielectric layers 56 on the TFT substrate 8.

[0093] It is desirable for the CF-on-TFT structured MVA-LCD havinganother alignment regulation structure besides the protrusion 29 to usethis structure. In the TN mode LCD, for example, it is necessary toconsider the laminating accuracy at the time of laminating the resin CFlayers, the panel attaching accuracy and the necessary area forobtaining the enough height of the layer while the columnar spacer isformed by laminating the resin CF layers. It is necessary to enlarge thesectional area of resin CF layers for forming the columnar spacer,therefore, the problem that the aperture ratio of pixel has to decreaseis caused to the TN mode LCD.

[0094] On the other hand, there is no need to consider the panelattaching accuracy in the CF-on-TFT structure. However, the apertureratio of pixel is decreased by forming the BM layer to shade thedefective alignment of the liquid crystal in the vicinity of columnarspacer.

[0095] On the contrary, since the CF-on-TFT structured MVA-LCD has anormally black mode which always becomes black on the part of thedisplay where the pixel electrode does not exist, there is no need toform BM layers. Therefore, it is possible to suppress the decreasing ofaperture ratio of pixel. Moreover, since it is no need to consider thepanel attaching accuracy and the defective alignment of the liquidcrystal in the vicinity of columnar spacer, it is possible to form thecolumnar spacer with suppressing the decreasing of aperture ratio ofpixel.

[0096] (Embodiment 1-3)

[0097] A description will now be made with reference to FIGS. 19 through22 on a substrate for a liquid crystal display according to Embodiment1-3, a liquid crystal display having the same, and a method ofmanufacturing the same. FIG. 19 shows a configuration of the substratefor a liquid crystal display of the present embodiment and correspondsto FIG. 6A. FIG. 20 shows a section of the substrate for a liquidcrystal display taken along the line G-G in FIG. 19 and corresponds toFIG. 6B. As shown in FIGS. 19 and 20, a common electrode 18 is formed ona glass substrate 12 in a display area 38 and a frame region 40 on acommon electrode substrate 10. Linear protrusions 28 are formed on thecommon electrode 18 in the display area 38 at an angle to edges of thedisplay area 38. The linear protrusions 28 are formed by a bottom layermade of chromium (Cr) that is a light-blocking metal and a top layerwhich is a resist layer used for patterning Cr. A frame pattern 34 forshielding edges of the display area 38 from light is formed in the frameregion 40. A cross-shaped alignment mark 36 used for combining thecommon electrode substrate with a TFT substrate 8 (which is not shown inFIGS. 19 and 20) in a face-to-face relationship is formed on the glasssubstrate 10 on the left side of the frame region 40 in the figure. Theframe pattern 34 and alignment mark 36 are formed simultaneously withthe linear protrusions 28 from the same material.

[0098] A method of manufacturing the substrate for a liquid crystaldisplay of the present embodiment will now be described with referenceto FIGS. 21 and 22. For example, an ITO film having a thickness of 100nm is first formed on an entire surface of the glass substrate 12 andpatterned as shown in FIG. 21 to form the common electrode 18. Forexample, a Cr film having a thickness of 100 nm is then formed on theentire surface as shown in FIG. 22. Next, a resist is applied to theentire surface, exposed, and developed to form a predetermined resistpattern. Then, Cr is etched using the resist pattern as an etching maskto form the bottom layer of the linear protrusions 28, the frame pattern34, and the alignment mark 36. The resist pattern is then hardenedthrough post-baking to form the top layer of the linear protrusions 28.The common electrode substrate 10 of the present embodiment is completedthrough the above-described steps.

[0099] While a metal layer capable of blocking light such as Cr is usedto shield the frame region 40 from light or to allow the alignment mark36 to be visually recognized and a resist is used to form the linearprotrusions 28 in the present embodiment, the need for a metal layer forblocking light can be eliminated by using a black resist for forming anopaque film as the resist layer as shown in FIGS. 5 through 6B. An MVAtype liquid crystal display is in the normally black mode, and such ablack resist will sufficiently work if it has an OD-value (opticaldensity) on the order of 2.0.

[0100] As thus described, the present embodiment makes it possible toprovide a liquid crystal display having high luminance and preferabledisplay characteristics.

[0101] [Second Mode for Carrying Out the Invention]

[0102] A description will now be made with reference to FIGS. 23 and 24on a substrate for a liquid crystal display on a second mode forcarrying out the invention, a liquid crystal display having the same,and a method of manufacturing the same.

[0103] Color liquid crystal displays are used as monitors and displaysof notebook PCs, PDAs (personal digital assistants), and the like, andthere are recent demands for further reductions in the weight of suchdisplays. In general, glass substrates occupy a great percentage of theweight of a liquid crystal display compared to other members. Forexample, glass substrates having a thickness of 0.7 mm occupy about 40%of the weight of a liquid crystal display. It is a common and effectiveapproach to reduce the weight of glass substrates in order to reduce theweight of a liquid crystal display.

[0104] One means for reducing the weight of a glass is to reduce thethickness of the same. However, it is difficult to form TFTs and colorfilters on a thin glass through highly accurate patterning, and aproblem arises in that there is a limit on patterning accuracy. Whenglass substrates having different characteristics are used as a TFTsubstrate and a common electrode substrate provided in a face-to-facerelationship, a problem arises in that it is difficult to combine themtogether because of deformation of the substrates attributable to heator the like. Although the two substrates may be polished to reduce thethicknesses of them after the liquid crystal panel is completed, aproblem arises in that the manufacturing cost is increased.

[0105] Another method for reducing the weight of substrates is to useplastic substrates instead of glass substrates. However, this results inthe same problem as encountered in the case of thin glass substrates inthat it is difficult to form TFTs and color filters for which highlyaccurate patterning is required. Further, since such substrates aresoft, a problem arises in that they may be insufficient in resistance topressures applied by fingers and the like depending on the intendedusage. It is an object of the present mode for carrying out theinvention to provide a lightweight liquid crystal display having highreliability.

[0106] Taking those problems into consideration, in the present mode forcarrying out the invention, TFTs and color filters are formed on onesubstrate. Since this eliminates the need for highly accurate patterningon another substrate, thin glass substrates, plastic substrates or thelike may be freely chosen. Further, columnar spacers for maintaining acell gap are formed on a substrate in advance in the present mode forcarrying out the invention. This makes it possible to provide a stablecell gap and to improve anti-pressure properties.

[0107] A more specific description will be made on substrates for aliquid crystal display in the present mode for carrying out theinvention, liquid crystal displays having the same, and methods ofmanufacturing the same with reference to Embodiments 2-1 and 2-2.

[0108] (Embodiment 2-1)

[0109] A liquid crystal display according to Embodiment 2-1 will now bedescribed. A TFT substrate 8 of the liquid crystal display of thepresent embodiment has a configuration similar to that of the TFTsubstrate 8 in the first mode for carrying out the invention shown inFIGS. 9 through 10B.

[0110]FIG. 23 corresponds to FIG. 10A and shows a section of the liquidcrystal display of the present embodiment. As shown in FIG. 23, theliquid crystal display of the present embodiment is formed by combininga TFT substrate 8 and a common electrode substrate 10 having a thicknesssmaller than that of the TFT substrate 8 with a predetermined cell gapkept between them. The common electrode substrate 10 has a commonelectrode 18 formed on a glass substrate 12′ having a thickness smallerthan that of a glass substrate 12 to serve as the TFT substrate 8.

[0111] A method of manufacturing a substrate for a liquid crystaldisplay according to the present embodiment and a liquid crystal displayhaving the same will now be briefly described. A method of manufacturingthe TFT substrate 8 will not be described because it is similar to thatin the first mode for carrying out the invention shown in FIGS. 11Athrough 16B. As shown in FIG. 23, a glass substrate 12′ made of nonalkali glass which is the same material as that of a glass substrate 12to serve as the TFT substrate 8 and which has a thickness smaller thanthat of the glass substrate 12, e.g., 0.2 mm, is used as the commonelectrode substrate 10. For example, an ITO film having a thickness of100 nm is formed on an entire surface of the glass substrate 12′ andpatterned to form a common electrode 18. This step completes the commonelectrode substrate 10.

[0112] Thereafter, alignment films are formed on surfaces of thesubstrates 8 and 10 in a face-to-face relationship and are rubbed. Next,a sealant is applied, and spacers are dispersed. The substrates 8 and 10are then combined and cut into each panel. Next, a liquid crystal isinjected through a liquid crystal injection port and sealed, andpolarizers are applied. A liquid crystal display according to thepresent embodiment is completed through the above-described steps.

[0113] While non alkali glass having a thickness of 0.2 mm is used asthe glass substrate 12′ of the present embodiment, glass having aspecific density different from that of the glass substrate 12 may beused instead. Soda lime glass including alkaline components may be usedto achieve a greater reduction in the manufacturing cost. For example,the glass includes 1% or more alkaline components. However, when glassincluding alkaline components is used in a liquid crystal display havingTFTs 42 of the channel-etching type or the like having exposed activesemiconductor layers 52, since the TFTs 42 can be contaminated byalkali, the TFTs 42 are preferably protected with a protective film orthe like. Such a problem will not occur when glass including alkalinecomponents is used in a liquid crystal display having TFTs 42 with achannel protection film.

[0114] In the present embodiment, resin CF layers R, G and B are formedon the TFT substrate 8 to allow the use of a substrate made of glass orplastic as the common electrode substrate 10. This makes it possible toprovide a lightweight and reliable liquid crystal display. Resistance topressures applied by fingers and the like can be improved by providing athicker substrate on the side of the display screen.

[0115] (Embodiment 2-2)

[0116] A liquid crystal display according to Embodiment 2-2 will now bedescribed with reference to FIG. 24. FIG. 24 is a sectional view of theliquid crystal display of the present embodiment showing a configurationof the same. As shown in FIG. 24, a common electrode substrate 10 of theliquid crystal display of the present embodiment has a glass substrate12′ having a thickness smaller than that of a glass substrate 12 toserve as a TFT substrate 8 just as in the liquid crystal display ofEmbodiment 2-1.

[0117] Resin CF layers B, G and R are formed in the same order on theTFT substrate 8, and resin layers 60 made of photosensitive acrylicresin are formed on the same to form columnar spacers 30 for maintaininga cell gap. The layers of the columnar spacers 30 may be in otherconfigurations, and the layers may be formed in any order. In the caseof an MVA type liquid crystal display, the resin layers 60 may be formedsimultaneously with linear protrusions as alignment regulatingstructures from the same material as that of the latter.

[0118] In the present embodiment, the use of the columnar spacers 30prevent any variation of the cell gap attributable to spherical spacersor the like dispersed on a substrate surface which can be stranded onalignment regulating structures, and this makes it possible to provide astable cell gap. Further, since the columnar spacers 30 are provided onthe substrate surface uniformly and in a high density, anti-pressureproperties are improved. For this reason, a reliable liquid crystaldisplay can be provided even when the common electrode substrate 10 isprovided on the display screen side. When the TFT substrate 8 isprovided on the display screen side, since reflection is increased bythe metal layer, it is desirable to use a low-reflection multi-layermetal at least on the side of the metal layer facing the glass substrate12.

[0119] Effects of the present mode for carrying out the invention willnow be specifically described in comparison to those of a conventionalliquid crystal display. Table 1 specifies two substrates A1 and B1 thatform a part of a conventional liquid crystal display. Resin CF layers R,G and B are formed on the substrate A1, and TFTs 42 are formed on thesubstrate B1. The substrates A1 and B1 are made of NA35 glass. Thesubstrates A1 and B1 have a thickness of 0.7 mm and a density of 2.50g/cm³. TABLE 1 Components Panel Thickness Density on Weight Material(mm) (g/cm³) Substrates Percentage Substrate NA35 glass 0.7 2.50 CF 1 A1Substrate NA35 glass 0.7 2.50 TFT B1

[0120] Table 2 specifies two substrates A2 and B2 that form a part ofanother conventional liquid crystal display. NA35 glass having a densityof 2.50 g/cm³ is used for both of the substrates A2 and B2 similarly tothe substrates A1 and B1. After they are combined, each of thesubstrates A2 and B2 is polished to a thickness of 0.5 mm. Resin CFlayers R, G and B are formed on the substrate A2, and TFTs 42 are formedon the substrate B2. Although a reduction in weight has been achieved inthe resultant panel in that it has a weight percentage of 0.71(hereinafter referred to as “panel weight percentage”) where it isassumed that a liquid crystal panel obtained by combining the substratesA1 and B1 shown in Table 1 has a weight percentage of 1, the panel ismore expensive because of an increase in the manufacturing cost. TABLE 2Components Panel Thickness Density on Weight Material (mm) (g/cm³)Substrates Percentage Substrate NA35 glass 0.5 2.50 CF 0.71 A2 SubstrateNA35 glass 0.5 2.50 TFT B2

[0121] Table 3 specifies two substrates A3 and B3 that form a part of aliquid crystal display according to the present embodiment. NA35 glasshaving a thickness of 0.7 mm and a density of 2.50 g/cm³ is used for thesubstrate B3 similarly to the substrate B1. TFTs 42 and resin CF layersR, G and B are formed on the substrate B3. Asahi AS glass that is alkaliglass having a thickness of 0.2 mm and a density of 2.49 g/cm³ is usedfor the substrate A3. The resultant panel has a weight percentage of0.64 which represents a weight smaller than that of the panel shown inTable 2. The substrate A3 may be made of any type of glass that islighter than the substrate B3. TABLE 3 Components Panel ThicknessDensity on Weight Material (mm) (g/cm³) Substrates Percentage SubstrateAsahi AS 0.2 2.49 — 0.64 A3 Substrate NA35 glass 0.7 2.50 TFT B3 CF

[0122] Table 4 specifies two substrates A4 and B4 that form a part ofanother liquid crystal display according to the present embodiment. NA35glass having a thickness of 0.7 mm and a density of 2.50 g/cm³ is usedfor the substrate B4 similarly to the substrate B1. TFTs and colorfilters are formed on the substrate B4. Polyethersulfone (PES) having athickness of 0.2 mm and a density of 1.40 g/cm³is used for the substrateA4. The resultant panel has a weight percentage of 0.58 which representsa greater reduction in weight than that of the panel shown in Table 3.The material of the substrate A4 is not limited to PES and may be anyplastic such as polycarbonate (PC) or polyacrylate (PAR). TABLE 4Components Panel Thickness Density on Weight Material (mm) (g/cm³)Substrates Percentage Substrate PES 0.2 1.40 — 0.58 A4 Substrate NA35glass 0.7 2.50 TFT B4 CF

[0123] As described above, the resin CF layers R, B and G are formedunder the pixel electrodes 14 in the present mode for carrying out theinvention. This eliminates any need for highly accurate patterning ofthe common electrode substrate 10 and also eliminates any need foraccurate alignment when combining it with the TFT substrate 8. Sincethis makes it possible to use a glass substrate, plastic substrate, orthe like having a small thickness as the common electrode substrate 10,a lightweight and reliable liquid crystal display can be provided.Further, since there is no need for polishing the TFT substrate 8 andcommon electrode substrate 10 to reduce their thickness after combiningthem, there is no increase in manufacturing steps and manufacturingcost.

[0124] [Third Mode for Carrying Out the Invention]

[0125] A description will now be made with reference to FIGS. 25 through34B on a substrate for a liquid crystal display, a liquid crystaldisplay having the same, and a method of manufacturing the same.

[0126] In the case of a substrate for a liquid crystal display having astructure in which resin CF layers R, G and B are formed on a TFTsubstrate 8 (CF-on-TFT structure) as in the first mode for carrying outthe invention, the numerical aperture can be improved because the resinCF layers R, G and B are formed under pixel electrodes 14. This improvesthe transmittance of the panel and makes it possible to improve theluminance of the liquid crystal display.

[0127] However, in a substrate for a liquid crystal display having theCF-on-TFT structure as in the first mode for carrying out the invention,if the top of the source/drain metal layers which are the top layer (Agate metal layer may be also included in the top layer in the case of atop gate structure. Hereinafter, such a configuration will be alsosimply referred to as “source/drain metal layers”.) is not covered by aprotective film (passivation film) when the TFTs 42 are formed, thesource/drain metal layers can be corroded by a CF developer when theresin CF layers R, G and B formed above the same are patterned, whichresults in a problem in that the resistance of the bus lines constitutedby the metal layers is increased and in that the bus lines are broken.Another problem arises in that the source electrodes 44 and drainelectrodes 46 are removed as a result of corrosion to expose the activesemiconductor layer 52 which can then be contaminated as a result ofcontact with the CF developer. When a protective film is formed on thesource/drain metal layer using a CVD apparatus, another problem arisesin that there will be an increase in the number of manufacturing steps.It is an object of the present mode for carrying out the invention toprovide a substrate for a liquid crystal display with which aninexpensive and reliable display can be provided, a liquid crystaldisplay having the same, and a method of manufacturing the same.

[0128] In the present mode for carrying out the invention, theabove-mentioned problems are solved by covering source/drain metallayers with resin CF layers R, G and B which are first formed or blackmatrix resin formed under the resin CF layers R, G and B or resin thatformed a part of columnar spacers 30.

[0129] A more specific description will now be made with reference toEmbodiment 3-1 and Embodiment 3-2 on substrates for a liquid crystaldisplay in the present invention, liquid crystal displays having thesame, and methods of manufacturing the same.

[0130] (Embodiment 3-1)

[0131] A description will be first made on a substrate for a liquidcrystal display according to Embodiment 3-1, a liquid crystal displayhaving the same, and a method of manufacturing the same with referenceto FIGS. 25 through 33B. FIG. 25 shows a configuration of the substratefor a liquid crystal display according to the present embodiment (CFlayers are omitted in the figure). FIG. 26A shows a section of thesubstrate for a liquid crystal display taken along the line J-J in FIG.25, and FIG. 26B shows a section of the substrate for a liquid crystaldisplay taken along the line K-K in FIG. 25. As shown in FIGS. 26A and26B, in the substrate for a liquid crystal display, a black matrix isformed by forming two resin CF layers in different colors at edges ofpixel regions. Throughout the black matrix formed by overlapping tworesin CF layers, a resin CF layer R is located at the bottom thereof.The resin CF layers R are formed such that they cover all ofsource/drain metal layers such as drain bus lines 26. A pixel electrode14 is formed with a slit 20 extending in parallel with an edge of thepixel region and a plurality of finer slits 21 diagonally extending fromthe slit 20. The substrate for a liquid crystal display of the presentembodiment has a liquid crystal in which a polymeric structure is formedby curing ultraviolet monomers through irradiation with ultravioletlight.

[0132] A method of manufacturing the substrate for a display of thepresent embodiment will now be described with reference to FIGS. 27through 33B. FIGS. 27 through 30 illustrate a method of manufacturingthe substrate for a liquid crystal display of the present embodiment.FIGS. 31A through 33B are sectional views at manufacturing stepsillustrating the method of manufacturing the substrate for a liquidcrystal display of the present embodiment. FIGS. 31A, 32A and 33A show asection similar to that in FIG. 26A, and FIGS. 31B, 32B and 33B show asection similar to that in FIG. 26B. Steps up to the formation of TFTs42 and drain bus lines 26 on a glass substrate 12 will not be describedbecause they are similar to those in the method of manufacturing thesubstrate for a liquid crystal display of Embodiment 1-1 shown in FIGS.11A through 13B.

[0133] At steps as shown in FIGS. 11A through 13B, a plurality of gatebus lines 25 extending in the horizontal direction in the figures anddrain bus lines 26 extending in the vertical direction in the figuresacross the gate bus lines 25 are formed (see FIG. 27). TFTs 42 areformed in the vicinity of intersections between the gate bus lines 25and drain bus lines 26. The gate bus lines 25 and drain bus lines 26define pixel regions. Storage capacity bus lines (auxiliary capacityelectrodes) 62 extending through the pixel regions substantially in themiddle thereof and substantially in parallel with the gate bus lines 25are formed in the same layer as that of the gate bus lines 25. A storagecapacity electrode (intermediate electrode) 64 for each pixel region isformed on the storage capacity bus line 62 in the same layer as that ofthe drain bus lines 26.

[0134] Next, a photosensitive red resist having a pigment dispersedtherein is applied to a thickness of 1.5 μm for example and patterned.It is thereafter subjected to post-baking to form first resin CF layersR on pixel regions to display red, the TFTs 42, the gate bus lines 25,the drain bus lines 26 and the storage capacity bus lines 62 as shown inFIGS. 28, 31A and 31B. At this time, the drain electrodes 44, sourceelectrodes 46 and drain bus lines 26 that are top metal layers arecovered by the resin CF layers R.

[0135] Next, a green resist is applied to a thickness of 1.5 μm forexample and patterned. It is thereafter subjected to post-baking to formsecond resin CF layers G on pixel regions to display green and on thedrain bus lines 26 located adjacently to such pixel regions on the leftof the same, as shown in FIGS. 29, 32A and 32B. At this time, a blackmatrix is formed by overlapping two resin CF layers on the TFTs 42 inthe pixel regions, the gate bus lines 25 adjacent to the pixel regions,the storage capacity bus lines 62 in the pixel regions, and the drainbus lines 26 located adjacently to the pixel regions on the left of thesame.

[0136] Next, a blue resist is applied to a thickness of 1.5 μm forexample and patterned. It is thereafter subjected to post baking to formthird resin CF layers B on pixel regions to display blue, the drain buslines 26 located adjacently to such pixel regions on both sides of thesame, and the TFTs 42 located adjacently to the pixel regions on theright of the same, as shown in FIGS. 30, 33A and 33B. At this time, ablack matrix is formed by overlapping two resin CF layers on the TFTs 42in the pixel regions located adjacently to the pixel regions on theright of the same, the gate bus lines 25 adjacent to the pixel regions,the storage capacity bus lines 62 in the pixel regions, and the drainbus lines 26 located adjacently to the pixel regions on both sides ofthe same.

[0137] Thereafter, an ITO film having a thickness of 70 nm for exampleis formed on the entire surface and patterned to form a pixel electrode14, a slit 20 and finer slits 21 in each pixel region, which completes asubstrate for a liquid crystal display as shown in FIGS. 25 through 26B.

[0138] Next, a vertical alignment film is applied to each of surfaces ofa common electrode substrate formed with a common electrode made of ITOfor example and the above-described substrate for a liquid crystaldisplay, the surfaces facing each other. For example, spherical spacersare then dispersed on one of the substrates, and a sealant is applied tothe periphery of the other substrate. Subsequently, the two substratesare put together, and a liquid crystal is injected into a gap betweenthe substrates. Referring to the liquid crystal, for example, a negativeliquid crystal having negative dielectric anisotropy added with 0.2%ultraviolet-curing monomer by weight may be used. Next, for example, atone voltage of 10 V dc is applied to the drain bus lines 26, and acommon voltage of 5 V dc is applied to the common electrode.Subsequently, for example, a gate voltage of 30 V dc is applied to thegate bus lines 25 to tilt the liquid crystal in the liquid crystal panelwhich is then irradiated with ultraviolet light of 2000 mJ having awavelength in the range from 300 to 450 nm from the opposite substrateside. As a result, the ultraviolet-curing monomers are cured to form apolymeric structure in the liquid crystal in the liquid crystal panel,which causes the liquid crystal molecules (represented by columns in thedrawings) to be tilted in four directions from their states when novoltage is applied, as shown in FIG. 25. In the present embodiment, thepre-tilt angle of the liquid crystal molecules is 86 deg. Thereafter,polarizers are applied to the two substrates to complete the liquidcrystal display of the present embodiment.

[0139] (Embodiment 3-2)

[0140] A description will be first made on a substrate for a liquidcrystal display according to Embodiment 3-2, a liquid crystal displayhaving the same, and a method of manufacturing the same with referenceto FIGS. 34A and 34B. FIGS. 34A and 34B are sectional views of thesubstrate for a liquid crystal display of the present embodiment showinga configuration of the same. While the substrate for a liquid crystaldisplay of Embodiment 3-1 has TFTs 42 with a channel protection film,the substrate for a liquid crystal display of the present embodiment haschannel-etched TFTs 66 as shown in FIGS. 34A and 34B.

[0141] A description will now be made on a substrate for a liquidcrystal display according to the present embodiment, a liquid crystaldisplay having the same, and a method of manufacturing the same. First,for example, an Al layer having a thickness of 100 nm and a Ti layerhaving a thickness of 50 nm are formed in the same order on an entiresurface of a glass substrate 12 and are patterned to form gate bus lines25 and storage capacity bus lines. Next, for example, a SiN film havinga thickness of 350 nm, an a-Si layer having a thickness of 120 nm, andan n⁺a-Si layer having a thickness of 30 nm are continuously formed.Next, the n⁺a-Si layer and a-Si layer are patterned in the form ofislands to form active semiconductor layers 52′ and n-type semiconductorlayers (not shown) located on the same. Next, for example, a MoN filmhaving a thickness of 50 nm, an Al film having a thickness of 150 nm, aMoN film having a thickness of 70 nm, and a Mo film having a thicknessof 10 nm are continuously formed and patterned, and element isolation isthen carried out to form source electrodes 46, drain electrodes 44, andstorage capacity electrodes. The channel-etched TFTs 66 are completedthrough the above-described steps. Subsequent steps are not illustratedand described because they are similar to those in the method ofmanufacturing the liquid crystal display of Embodiment 3-1 shown inFIGS. 27 through 33B.

[0142] A method of manufacturing a substrate for a liquid crystaldisplay according to another embodiment of the invention will now bedescribed. Although not shown, features having the same functions andoperations as those of the features shown in FIGS. 34A and 34B will bedescribed using like reference numbers. The substrate for a liquidcrystal display of the present embodiment has top-gate type TFTs 42.First, for example, a Ti layer having a thickness of 20 nm, an Al layerhaving a thickness of 75 nm, a Ti layer having a thickness of 40 nm, andan n⁺a-Si layer having a thickness of 30 nm are formed on a glasssubstrate 12 and are patterned to form drain electrodes 44 and sourceelectrodes 46. Next, for example, an a-Si layer having a thickness of 30nm, a SiN film having a thickness of 350 nm, and an Al layer having athickness of 100 nm are formed and patterned to form activesemiconductor layers 52′, an insulation film 24, and gate bus lines 25simultaneously. The semiconductor layers 52′, insulation films 24, andgate bus lines 25 may be sequentially formed instead of forming themsimultaneously. The top-gate type TFTs 42 are completed through theabove-described steps. Although storage capacity bus lines 62 andstorage capacity electrodes 64 are not formed in the present embodiment,they may be obviously formed. Subsequent steps will not be describedbecause they are substantially similar to those of the method ofmanufacturing the liquid crystal display of Embodiment 3-1 shown inFIGS. 27 through 33B. In the present embodiment, since the top metallayer is the gate metal layer, the gate metal layer is coated with theresin CF layer that is formed first.

[0143] A method of manufacturing a substrate for a liquid crystaldisplay according to still another embodiment of the invention will nowbe described. Although not shown, features having the same functions andoperations as those of the features shown in FIGS. 34A and 34B will bedescribed using like reference numbers. The substrate for a liquidcrystal display of the present embodiment has TFTs in which polysilicon(p-Si) is used for active semiconductor layers 52. First, for example, aSiN film having a thickness of 50 nm, a SiO₂ film having a thickness of200 nm, and an a-Si layer having a thickness of 40 nm are formed on aglass substrate 12, and the resultant substrate is subjected to a heattreatment in an annealing oven to be dehydrogenized. Next, the a-Silayer is irradiated with a predetermined laser to be crystallized and isthen patterned to form a p-Si layer. Next, for example, a SiO₂ filmhaving a thickness of 110 nm and a AlNd film having a thickness of 300nm are formed and patterned to form insulation films (gate insulationfilms) 24 and gate bus lines 25.

[0144] The p-Si layer is then doped with phosphorus (P) ions to formN-type regions selectively, and the p-Si layer is subsequently dopedwith boron (B) ions to form P-type regions selectively. Next, forexample, a SiO₂ film having a thickness of 60 nm and a SiN film having athickness of 370 nm are formed to form an interlayer insulation film.The interlayer insulation film on the high density impurity regions isthen removed to form contact holes. Next, for example, a Ti layer havinga thickness of 100 nm, an Al layer having a thickness of 200 nm, and aTi layer having a thickness of 100 nm are formed and patterned to formdrain electrodes 44 and source electrodes 46. TFTs 70 in which p-Si isused for active semiconductor layers are completed through theabove-described steps. Although storage capacity bus lines and storagecapacity electrodes are not formed in the present embodiment, it isobviously possible to form storage capacity bus lines simultaneouslywith the gate bus lines from the same material and to form storagecapacity electrodes simultaneously with the source and drain electrodesfrom the same material.

[0145] While the top metal layer is covered by the resin CF layer thatis formed first in the above-described embodiment, the top metal layermay be covered by resin to serve as a black matrix or resin to serve asa part of columnar spacers before the resin CF layer is formed. While ablack matrix is formed by laminating two resin CF layers, i.e., thefirst and second resin CF layers or the first and third resin CF layerson the TFTs 42 and bus lines 25, 26, and 62 in the above-describedembodiment, the black matrix may be formed by staking all of the threeresin CF layers. It is not necessary to form the resin CF layers ifblack matrix is formed at a different step.

[0146] Further, while the pixel electrodes 14 in the above-describedembodiment are formed with the slits 20 and finer slits 21 because thedescribed example is a polymer-fixed liquid crystal display, otheralignment regulating structures may be used. While the entire top metallayer is covered with a resin CF layer in the above-describedembodiment, only edge portions of the top metal layer may be covered.Obviously, the substrate for a liquid crystal display may have astructure which does not include the storage capacity bus lines 62 madeof the same material as that of the gate bus lines 25 and the storagecapacity electrodes 64 made of the same material as that of the sourceelectrodes 44 and drain electrodes 46.

[0147] As described above, in the present mode for carrying out theinvention, the source/drain metal layer (a gate metal layer in the caseof a top-gate structure) is covered by the resin CF layer that is formedfirst. This prevents the source/drain layer from being corroded by a CFdeveloper when the resin CF layers are patterned. Since this preventsany increase in the bus line resistance and breakage of the bus lines,an improved yield of manufacture can be achieved. Further, the activesemiconductor layers 52 will not be contaminated. There is no increasein the number of manufacturing steps because it is not necessary to forma protective film on the source/drain metal layer.

[0148] The liquid crystal display in the present mode for carrying outthe invention is free from any reduction or irregularity of luminanceattributable to a reduction in retention and burning of patterns. Sincethe resin CF layers R, G and B formed on the TFTs 42 absorb ultravioletlight applied to form a polymeric structure, there will be no displaydefect such as cross-talk or a flicker which is otherwise caused byabnormality in the characteristics of the TFTs 42.

[0149] Since the alignment of liquid crystal molecules is separated infour directions in the liquid crystal display in the present mode forcarrying out the invention, a wide viewing angle is provided, and highcontrast can be achieved by vertical alignment. Further, since thetilting direction of liquid crystal molecules is regulated by apolymeric structure, high speed response can be achieved.

[0150] The invention is not limited to the above-described modes forcarrying out the same may be modified in various ways.

[0151] For example, the pixel electrodes 14 are formed directly on theresin CF layers R, G and B in the above-described modes for carrying outthe invention. The invention is not limited to such a configuration, anda protective film made of an organic or inorganic material may be formedon the resin CF layers R, G and B, and the pixel electrodes 14 may beformed on the protective film. The formation of such a protective filmmakes it possible to prevent the liquid crystal from being contaminatedby the material of the resin CF layers and to prevent line breakagethrough a reduction in steps at the pixel electrodes 14. The resin CFlayers R, G and B may be formed in any order, and the materials,configurations and thicknesses of the TFTs 42 and resin CF layers R, Gand B are not limited to those described in the above modes for carryingout the invention.

[0152] While transmission type liquid crystal displays have beenreferred to in the above-described modes for carrying out the invention,the invention is not limited to them and may be applied to reflectiontype liquid crystal displays. While MVA type liquid crystal displayshave been referred to in the above-described modes for carrying out theinvention, the invention is not limited to them and may be applied toliquid crystal displays in other modes such as the TN mode.

[0153] As thus described, the present invention makes it possible toprovide a liquid crystal display having high luminance and preferabledisplay characteristics.

What is claimed is:
 1. A liquid crystal display substrate, comprising: asubstrate which sandwiches a liquid crystal having negative dielectricanisotropy in combination with an opposite substrate provided in aface-to-face relationship therewith; a plurality of gate bus linesformed on the substrate; a plurality of drain bus lines formed on thesubstrate such that they intersect the gate bus lines; pixel regionsdefined by the gate bus lines and the drain bus lines; a thin filmtransistor formed in each of the pixel regions; a resin color filterlayer formed in each of the pixel regions; a pixel electrode formed ineach of the pixel regions; and an alignment regulating structure formedon the substrate for regulating the alignment of the liquid crystal. 2.A liquid crystal display substrate according to claim 1, furthercomprising an opaque film for shielding edges of the pixel regions fromlight.
 3. A liquid crystal display substrate according to claim 2,wherein the opaque film is formed by laminating the resin color filterlayers.
 4. A liquid crystal display substrate according to claim 1,wherein the pixel electrode is formed on the resin color filter layer.5. A liquid crystal display substrate according to claim 4, wherein thepixel electrode is formed such that the electrode overlaps the drain buslines when viewed in a direction perpendicular to a surface of thesubstrate.
 6. A liquid crystal display substrate according to claim 4,wherein the pixel electrode is formed such that the electrode does notoverlap the drain bus lines when viewed in a direction perpendicular toa surface of the substrate.
 7. A liquid crystal display substrateaccording to claim 1, wherein the alignment regulating structure is alinear protrusion.
 8. A liquid crystal display substrate according toclaim 1, further comprising a columnar spacer for maintaining a cellgap, the columnar spacer being formed by laminating resin layers formedon the substrate.
 9. A liquid crystal display substrate according toclaim 8, wherein the resin layers include the resin color filter layers.10. A liquid crystal display substrate according to claim 8, wherein theresin layers include a black resin layer.
 11. A liquid crystal displaysubstrate according to claim 8, wherein the resin layers include a layerin which the linear protrusion is formed.
 12. A liquid crystal displaysubstrate, comprising: a substrate which sandwiches a liquid crystalhaving negative dielectric anisotropy in combination with an oppositesubstrate provided in a face-to-face relationship therewith; a linearprotrusion formed on the substrate for regulating the alignment of theliquid crystal; and an alignment mark which is formed on the substratefrom the same material as that of the linear protrusion and which isused for combining the substrate with the opposite substrate.
 13. Aliquid crystal display substrate according to claim 12, wherein theprotrusion is formed of black resin.
 14. A liquid crystal displaysubstrate according to claim 12, wherein the protrusion is formed bylaminating a metal layer and a resist layer.
 15. A liquid crystaldisplay substrate, comprising: a substrate which sandwiches a liquidcrystal having negative dielectric anisotropy in combination with anopposite substrate provided in a face-to-face relationship therewith; alinear protrusion formed on the substrate for regulating the alignmentof the liquid crystal; and a frame region which is formed at edges of adisplay area on the substrate from the same material as that of thelinear protrusion and which shields the edges of the display area fromlight.
 16. A liquid crystal display substrate according to claim 15,wherein the protrusion is formed of black resin.
 17. A liquid crystaldisplay substrate according to claim 15, wherein the protrusion isformed by laminating a metal layer and a resist layer.
 18. A liquidcrystal display comprising two substrates and a liquid crystal sealedbetween the substrates, wherein a liquid crystal display substrateaccording to claim 1 is used as at least either of the substrates.
 19. Aliquid crystal display comprising: a first substrate having a firstresin layer formed thereon; a second substrate having a second resinlayer formed thereon; a columnar spacer formed as a combination of thefirst and second resin layers by combining the first and secondsubstrates; and a liquid crystal sealed between the first and secondsubstrates.
 20. A method of manufacturing a substrate for a liquidcrystal display, comprising the steps of: forming a common electrode ona substrate; and forming an alignment mark on the substrate at the sametime when a linear protrusion is formed on the common electrode.
 21. Amethod of manufacturing a substrate for a liquid crystal display,comprising the steps of: forming a common electrode on a substrate; andforming frame region on the substrate at the same time when a linearprotrusion is formed on the common electrode.
 22. A method ofmanufacturing a substrate for a liquid crystal display, comprising thesteps of: forming a plurality of bus lines intersecting each other and athin film transistor on a substrate; and forming a columnar spacer atthe same time when a linear protrusion is formed on the substrate.
 23. Aliquid crystal display comprising: a thin film transistor substrateincluding a first substrate, a plurality of bus lines formed on thefirst substrate such that they intersect each other, pixel regionsdefined by the bus lines, a thin film transistor formed in each of thepixel regions, a resin color filter layer formed in each of the pixelregions, and a pixel electrode formed in each of the pixel regions; acommon electrode substrate including a second substrate different fromthe first substrate in the thickness or material and a common electrodeformed on the second substrate, the common electrode substrate beingprovided in a face-to-face relationship with the first substrate; and aliquid crystal sealed between the thin film transistor substrate and thecommon electrode substrate.
 24. A liquid crystal display according toclaim 23, wherein the second substrate has a thickness smaller than thatof the first substrate.
 25. A liquid crystal display according to claim23, wherein the second substrate is lighter than the first substrate.26. A liquid crystal display according to claim 23, wherein the secondsubstrate is formed from a glass material including alkaline components.27. A liquid crystal display according to claim 26, wherein the glassmaterial includes 1% or more alkaline components.
 28. A liquid crystaldisplay according to claim 23, wherein the second substrate is formedfrom a resin material.
 29. A liquid crystal display according to claim23, further comprising a columnar spacer for maintaining a gap betweenthe thin film transistor substrate and the common electrode substrate.30. A liquid crystal display according to claim 23, wherein the thinfilm transistor substrate is located closer to a display side.
 31. Aliquid crystal display according to claim 30, wherein at least surfacesof the bus lines facing the first substrate is formed from a lowreflection material.
 32. A liquid crystal display according to claim 30,wherein at least surfaces of a drain electrode and a source electrode ofthe thin film transistor facing the first substrate are formed from alow reflection material.
 33. A liquid crystal display substrate,comprising: a substrate which sandwiches a liquid crystal in combinationwith an opposite substrate provided in a face-to-face relationshiptherewith; a plurality of gate bus lines formed on the substrate; aplurality of drain bus lines formed on the substrate such that theyintersect the gate bus lines; pixel regions defined by the gate buslines and the drain bus lines; a thin film transistor formed in each ofthe pixel regions; a resin color filter layer formed in each of thepixel regions; a pixel electrode formed in each of the pixel regions;and a resin layer formed to cover source and drain electrodes of thethin film transistor and the drain bus lines.
 34. A liquid crystaldisplay substrate according to claim 33, wherein the resin layer isconstituted by the resin color filter layer.
 35. A liquid crystaldisplay substrate according to claim 34, wherein a resin color filterlayer in a different color is laminated on the resin layer.
 36. A liquidcrystal display substrate according to claim 33, wherein the resin layerincludes black resin.
 37. A liquid crystal display substrate accordingto claim 33, wherein the resin layer includes a layer to form a columnarspacer.
 38. A liquid crystal display comprising two substrates and aliquid crystal layer sealed between the substrates, a substrate for aliquid crystal display according to claim 33 being used as either of thesubstrates.
 39. A liquid crystal display according to claim 38, whereina polymeric structure is formed in the liquid crystal layer.
 40. Amethod of manufacturing a substrate for a liquid crystal display,comprising the steps of: forming a thin film transistor on a substrate;forming a first resin color filter layer such that the color filterlayer covers source and drain electrodes of the thin film transistor anda drain bus line; forming a second resin color filter layer in anotherpixel region; and forming a third resin color filter layer in stillanother pixel region.